It is known in the printing industry that a printing plate having a photohardenable surface layer can be exposed through an image bearing transparency to generate imagewise hardened regions. The exposed plate is then developed in an appropriate solvent to remove unexposed polymer through the action of the solvent alone or in conjunction with a mechanical scrubbing action. Depending on the particular photohardenable element, its chemical composition and the method of development, it is sometimes necessary to reduce tack on the surface of the element in a finishing treatment.
Available finishing equipment includes a large tray that holds the solution in which a developed plate is immersed by an operator and from which the plate must be removed on time. Then, the plate is rinsed with tap water and dried. As a practical matter, this equipment requires continuous attendance by an operator. Although exhaust ducting is provided, there is always a possibility of exposure to objectionable fumes when a cover for the tray is raised and a plate is being immersed.